The objective of this program is to provide efficient synthetic methods for the synthesis of steroid and terpenoid-like molecules of medicinal and biological interest. A scheme is described for the homoannelation and alkylation of alpha-methylene ketones that will efficiently produce various tricyclic systems amenable to further elaboration toward the tetracyclic steroid-terpenoid systems. In this manner, molecules that have varying degrees of substitution and stereochemistry about the backbone of the tetracyclic nucleus will become available. The method will be used to make variations of the estrone molecule as well as the trans-syn-trans nucleus of the antibiotic fusidic acid and several sterol biosynthetic intermediates. Through these syntheses, molecules that may be more pharmaceutically specific than the naturally occurring steroids and terpenoids will become available. The substances produced may also have significant anti-tumor activity and can be evaluated for this purpose.